Submicron polyacrolein particles in situ embedded with upconversion nanoparticles for bioassay

Abstract

We report a new surface modification approach of upconversion nanoparticles (UCNPs) structured as inorganic hosts NaYF4 codoped with Yb(3+) and Er(3+) based on their encapsulation in a two-stage process of precipitation polymerization of acrolein under alkaline conditions in the presence of UCNPs. The use of tetramethylammonium hydroxide both as an initiator of acrolein polymerization and as an agent for UCNP hydrophilization made it possible to increase the polyacrolein yield up to 90%. This approach enabled the facile, lossless embedment of UCNPs into the polymer particles suitable for bioassay. These particles are readily dispersible in aqueous and physiological buffers, exhibiting excellent photoluminescence properties, chemical stability, and also allow the control of particle diameters. The feasibility of the as-produced photoluminescent polymer particles mean-sized 260 nm for in vivo optical whole-animal imaging was also demonstrated using a home-built epi-luminescence imaging system.

Upconversion nanoparticles: on the way from diagnostics to theranostics

“…We exploited the original design of UCNP nanocomplexes, where a "corona" was obtained from chemically bound PEG molecules, in order to increase the circulation time in the blood system in vivo and deliver UCNPs to the tumor (Fig.1, way 2) [2]. UCNP encapsulation into polyacrolein particles in the course of radical heterophase polymerization was the basis for production the reagents capable to study the particle biodistribution by organs at intravenous injection (Fig.1, way 3) [3]. Unique optical properties of UCNPs enabled formation of hybrid nanocomplexes with riboflavin (Rf) responsible for generating active oxygen forms under the NIR-radiation through the realization of FRET effect.…”

Riboflavin photoactivation by upconversion nanoparticles for cancer treatment

“…In order to demonstrate that the high phototoxic value of C Rf is attainable in tumour interstitium, we carried out epi-luminescent imaging of a laboratory mouse bearing an induced Lewis lung cancer (see M&M). 3 mg of FMN (10 mg/mL, PBS buffer) was injected intravenously and 12 hours later the euthanised animal with a cancer site exposed surgically was imaged using a home-built epi-luminescent imaging system 17 (detailed in SI 4). A cuvette filled with 30-μM FMN aqueous solution was placed nearby for comparison (see Fig.…”

Radioactive ( 90 Y) upconversion nanoparticles conjugated with recombinant targeted toxin for synergistic nanotheranostics of cancer

“…TGI was calculated using the equation TGI = ðV control − V treatment Þ=V control × 100%, [4] where V is the average volume of the tumor node in the corresponding group. The time of the UCNP-R-T retention in the tumor was determined by means of the imaging of experimental tumors using a home-built whole-animal system (49), which allowed detection of photoluminescent signal at a wavelength of 800 nm upon the excitation at 980 nm. Images were taken using an electron multiplying charge-coupled devices (EMCCD) camera with a 2× magnification.…”